Idun know how to do this, it’s a simultaneous equation

can solve via substitution. if we rearrange the top equation:



we can substitute this into the bottom equation.



we need a common denominator to add fractions.

the lowest common denominator (for the left side of the equation) is  .

if we multiply the numerator and denominator of  by  and then multiply the numerator and denominator of  by  , both fractions will end up with the same denominator, allowing for addition of fractions.



factor  : find two numbers that multiply to get +12 (leading coefficient times constant) and add to get -7.

-4 and -3.

factor by decomposition: break down the middle term.





substitute these values into the first equation.

for  :



for  :



so solutions of 



and



can confirm that the solutions work by substituting each set back into the system to see if the equations are true.